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Quick answerHow is Lyme disease transmitted?
How you get Lyme disease, and what the evidence says about sex, pregnancy, breastfeeding, blood transfusions, pets and insects.
Quick answer
Lyme disease is transmitted by the bite of an infected blacklegged tick. The tick usually has to stay attached for more than 24 hours to pass on the bacteria. CDC finds no credible evidence of spread through sex, kissing, touching, mosquitoes, food, air or water. Passing it from mother to baby during pregnancy is possible but extremely rare.
- Lyme disease is spread through the bite of infected blacklegged ticks (CDC).
- Removing a tick within 24 hours greatly lowers the chance of infection.
- No credible scientific evidence shows spread person to person through touching, kissing or sex.
- No cases have been linked to blood transfusion, but the bacteria can survive in stored blood, so people on antibiotics for Lyme should not donate.
The main route: tick bites
Nearly every case starts with a bite from an infected blacklegged tick (deer tick) in the East and Midwest or a western blacklegged tick on the Pacific coast. The tick slowly feeds on blood. CDC says an infected tick generally needs to be attached for more than 24 hours before it passes the bacteria on, so a quick tick check after outdoor time makes a real difference.
Young ticks called nymphs cause many cases. They are about the size of a poppy seed and most active from April through July. Adult ticks, about the size of a sesame seed, are most active in early spring and fall. Learn more in how long a tick needs to be attached and what to do after a tick bite.
Can Lyme disease be sexually transmitted?
CDC states there is no credible scientific evidence that Lyme disease spreads through sex, kissing or touching. Animal studies also do not support sexual transmission. You may see claims online that it is a sexually transmitted infection; those claims are not supported by the evidence CDC has reviewed. See is Lyme disease contagious?
Pregnancy and breastfeeding
If Lyme disease is not treated during pregnancy, the bacteria can reach the placenta. CDC says spread from mother to unborn baby is possible but extremely rare. With the right antibiotics, CDC reports no increased risk of poor birth outcomes. Some antibiotics are not used in pregnancy, so tell your provider if you are pregnant.
There are no reports of Lyme disease spreading through breast milk. CDC advises breastfeeding parents diagnosed with Lyme disease to tell their provider so they can get an antibiotic that is safe while nursing.
Blood transfusions
No cases of Lyme disease have been linked to blood transfusion, according to CDC. However, the bacteria can survive in stored donor blood. That is why people being treated for Lyme disease should not donate blood. People who have finished treatment may be able to donate; blood banks set their own rules.
Pets, insects, food and air
- Pets: dogs and cats can get Lyme disease but do not appear to spread it directly to people. They can carry infected ticks into your home or yard. See Lyme disease in dogs.
- Mosquitoes, flies, fleas and lice: no credible evidence they spread it. See do mosquitoes carry Lyme disease?
- Air, food and water: no credible evidence. Eating game meat does not spread it, though meat should be cooked well, and hunters can be exposed to ticks when handling game.
- Other ticks: lone star, American dog, Rocky Mountain wood and brown dog ticks do not spread Lyme bacteria, but can spread other diseases.
We are collecting real experiences about how Lyme disease reached them from people who have lived it, shared with their permission. As stories come in, they will appear here, clearly marked as personal experience rather than medical advice.
Frequently asked questions
How do you get Lyme disease?
From the bite of an infected blacklegged tick that stays attached long enough to pass on the bacteria, usually more than 24 hours (CDC).
Can my partner give me Lyme disease?
CDC says there is no credible scientific evidence that Lyme disease spreads through sex, kissing or touching.
Can Lyme disease pass to a baby during pregnancy?
It is possible but extremely rare when the infection is untreated. With proper antibiotic treatment, CDC reports no increased risk of poor birth outcomes.
Can I donate blood if I had Lyme disease?
Not while you are being treated. People who have finished treatment may be considered as donors (CDC). Check your blood bank’s rules.